Merge contact shows 404 for some contacts that open on the profile

Let staff open the Merge contact flow for any contact they can view on the profile, so duplicates can be consolidated without a dead-end 404.
Show a clear error when merge truly cannot load (missing contact, permissions), instead of a generic 404 that looks like the contact does not exist.

In production, some contacts show a blank page with 404 in the browser tab when clicking Merge contact from the profile or contacts list. Other contacts merge normally.
Example contact (profile loads; merge fails): Contact profile → merge path: https://www.attik.ai/contacts/6a0c58c408bc100679748727/merge
Production routes www.attik.ai/contacts/* to the tools app via host rewrite in attik-frontend/next.config.js (destination: "/tools/:path*").
Likely cause (code review): The contact profile and merge pages both call GET contact/:id, but only the merge page validates the response with strict Zod (ContactWithBusinessPopulatedSchema) and calls notFound() on any failure—including validation errors. The profile page intentionally skips Zod (legacy/import field shapes). Legacy or imported contacts can therefore load on the profile but 404 on merge.
Confirmation step for QA: On a failing contact, DevTools → Network → GET contact/<id> on merge load. If status is 200 but the page is still 404, the failure is schema validation, not a missing contact.

Merge page load: attik-frontend/src/app/tools/contacts/[contact_id]/merge/page.tsx — fetches contact/${contact_id} with ContactWithBusinessPopulatedSchema; catch → notFound() (Next.js 404).
Profile page (works today): attik-frontend/src/app/tools/contacts/[contact_id]/page.tsx — same API call without Zod (comment notes skipped validation for volume metrics / legacy values).
Schema: attik-frontend/src/util/types/serverTypeCollection/contact.ts — strict fields that may fail on older rows include tags (required array), preferredContactMethod, emailStatus, smsStatus, active, createdAt, updatedAt, ccEmails refine, populated _contactBusinessId.
Entry points: ContactDetailsSection.tsx (Merge button, disabled when isDeleted), ContactActions.tsx (list merge action).
Error UI exists but not used for validation failures: merge/error.tsx (only for thrown errors in client tree, not server notFound()).
Decision needed: Align merge initial load with profile (lenient parse / safeParse + defaults), and/or relax/normalize schema for legacy contacts. Do not map validation failures to notFound().

attik-backend/src/routes/contact.ts — GET /:id via getSingleItem returns contact by Mongo id (404 only if doc missing); does not filter isDeleted on GET. Merge submit is POST /:id/merge (404 for missing secondary; 400 for deleted/already-merged)—out of scope for the page-load 404 unless investigation shows API 404 on GET for these ids.

Merge submit logic and inspection/quote transfer (already implemented on POST /:id/merge).
Contacts that are soft-deleted (isDeleted)—Merge is already disabled on the profile for those.

Attik